@literally45-- I think that true Kaseri is made with sheep's milk and the ones in Greece are usually mostly sheep's milk. But I have seen ones made with cow's milk. Cow's milk certainly makes for a milder testing cheese with less fat and many people do prefer it.
As far as I know, a lot of Kaseri cheese is made from unpasteurized milk. So if you buy it from a farmer, it probably has raw milk. But the ones sold in stores are usually pasteurized. You can either check the label or ask the seller what type of milk was used. If you are pregnant, don't eat Kaseri unless you're sure that it contains pasteurized milk. Raw milk can be dangerous for babies.